Abstract
Lever ratio of the ossicles and input impedance of the cochlea with the stapes were measured in nine human cadaver temporal bones using video measuring system. The cochlear impedance measurement was done immediately after the ossicular lever ratio measurement. The average lever ratio was about 10 dB at low frequencies and increased gradually above 1.4 KHz. The average cochlear impedance was 0.7 ± 0.3 MΩ at 1 KHz. There was no significant correlation between the lever ratio and cochlear impedance. Our results suggested that larger lever ratio doesn't always mean higher sound pressure transmission through the middle ear.
